The present invention is directed to a rolling protective shutter assembly which has a protective shutter, for covering a window or door opening, that may be rolled up into a shutter housing when not in use.
Rolling protective shutters are conventional and are used to provide protection against extreme weather conditions and to deter theft, for example. One such rolling protective shutter is disclosed in U.S. Pat. No. 5,575,322, issued to Miller on Nov. 19, 1996, entitled "Rolling Protective Shutters," which is hereby expressly incorporated by reference herein. As shown in FIGS. 1 and 2 of that patent, the Miller shutter is composed of a plurality of individual slats and a plurality of hinges interconnecting the slats. Each of the slats has a pair of end portions, and the slats include a first set of slats and a second set of slats, each of the slats in the first and second sets being alternated so that each of the hinges is connected to one of the slats in the first set and one of the slats in the second set. The shutter assembly has a pair of shutter tracks and means for rolling the shutter from an extended position in which the end portions of the slats are disposed in the shutter tracks to a retracted position in which the shutter is rolled up on a shutter support member. The hinges and the shutter tracks are adapted to facilitate, when the shutter is in the extended position, the slats in the first set of slats to occupy a first relative position and the slats in the second set of slats to occupy a second relative position.
In a conventional rolling shutter of the type in which the slats maintain a vertical position when the shutter is in its unrolled position, each side track for the rolling shutter forms a generally U-shaped channel for receiving the shutter slats, and includes a structural support member which forms a cavity running the entire length of the side track. The structural support member increases the strength of the side track in resisting forces applied to the shutter curtain, and provides a surface area for anchoring the side track against the frame of the opening covered by the shutter. The structural support member is also used to secure the shutter housing to the side track. As shown in FIG. 7, a prior art shutter housing 180 for a vertically-aligned slat shutter curtain 181 has an extension member 182, commonly referred to as an end cap nipple, extending therefrom on each end of the shutter housing 180. The shutter housing 180 is secured to a side track 184 by inserting the end cap nipple 182 into a cavity 186 created by a structural support member 188. The structural support member 188 frictionally engages the nipple 182 to prevent relative movement of the shutter housing 180 with respect to the side track 184.
In rolling shutter systems with vertically-aligned slats, the channel of the side tracks is dimensioned wide enough to accommodate the thickness of the shutter slats. These systems are typically divided into two types: mini systems, which use thinner slats, and maxi systems, which use slats that are thicker and stronger and require a slightly deeper side track. A standard-size nipple is used for both the mini and the maxi systems. The portion of the standard-size nipple extending from the shutter housing has a length a of approximately 21/2", a width b of approximately 7/8" and a thickness c of approximately 5/8". FIGS. 8(a) and (b) illustrate side tracks 190, 194 having accommodation fins 192, 196, respectively, that enable the use of the standard-size nipple with both systems.
The rolling shutters having an angular configuration such as those disclosed in the Miller patent, require side tracks with a significantly wider channel to accommodate the angular configuration of the shutter slats. As a result, the width of the channel is significantly larger than the thickness of the standard-size end cap nipple. This necessitates significant modifications of the side tracks to adequately retain the nipple within the structural support member of the side track, and to ensure that the side track is strong enough to withstand forces applied to the shutter curtain due to vandalism and adverse weather conditions.